Tetra



Black neon tetra, Hyphessobrycon herbertaxelrodi


Scientific classification





Kingdom:

Animalia



Phylum:

Chordata



Class:

Actinopterygii



Order:

Characiformes



Family:

Characidae
Alestiidae





 Pristella tetra—Pristella maxillaris.
Tetra is the common name for various small, often colorful, tropical, freshwater fish within the two characiform (order Characiformes) families Characidae—and in particularly its subfamily Tetragonopterinae, the "South American tetras"—and Alestiidae, the "African tetras." The African tetras formerly were classified in Alestiinae as a subfamily of Characidae, and remain within Characidae in some classifications.
The term tetra is not a formal taxonomic rank, but rather is the common name used for numerous small fish scattered over numerous genera and different families and subfamilies. Because of the popularity of tetras in the fish-keeping hobby, many unrelated fish are commonly known as tetras. Even fish that are vastly different may be called tetras, such as Hydrolycus scomberoides, occasionally known as the sabretooth tetra or vampire tetra, which is placed in the Characinae subfamily within Characidae.
Being small and brightly colored, and often easy to keep in captivity, many tetras, such as the neon tetra, Paracheirodon innesi, are extremely popular for home aquariums. Whether seen in aquariums or in the wild in a clear stream, tetras, add to the wonder of nature for humans. Tetras also are valuable ecologically due to their role in food chains, preying upon smaller invertebrates, such as insects, and being prey for larger fish, mammals, birds, and so forth.

Contents

1 Description
2 Tetra species
3 References
4 Credits


Description
 Golden Pristella tetra, a morph of Pristella maxillaris.
 Silver tipped tetra—Hasemania nana.
Tetras traditionally were classified within the family Characidae (characins), and in particularly the subfamilies Tetragonopterinae (South American tetras) and Alestiinae (African tetras). However, this family has undergone much taxonomic revision and many authorities have moved the African tetras to the family level, called Alestiidae (Nelson 2006).
Both Characidae and Alestiidae belong to the order Characiformes. Characiformes are characterized by well developed teeth (most are carnivores) and the presence of a pelvic fin (with five to twelve rays) and normally an adipose fin, and a body that is almost always scaled (Nelson 1994).
Characidae is a large and diverse family of freshwater subtropical and tropical fish, with members found in Central and South America, southern North America, and Africa, and include such varied forms as the piranhas, the tetras, a blind cavefish in Mexico (populations of Astyanax mexicanus found in caves) and Brazil (Stygichthys typhlops), and a species found as far northward as southwestern United States (Astyanax mexicanus) (Nelson 1994). The characins are distinguished from other fish by the presence of a small adipose fin between the dorsal fin and caudal fin. Both the Characidae family and the Alestiidae families are comprised only of freshwater fish.
The South American tetras, placed in the subfamily Tetragonopterinae within Characidae, comprise numerous genera, including Hemigrammus, Hyphessobrycon, Paracheirodon (the neon, green, and cardinal tetras), and Tetragonopterus.
The African tetras, now placed in the family Alestiidae, include 18 genera, including Alestes (=Brycinus) and Hydrocynus, with about 110 recognized species in total (Nelson 1994).

Tetra species
The following are some species with the common name of tetra. Though the list below is sorted by common name, in a number of cases, the common name is applied to different species, depending on country and context. Since the aquarium trade may use a different name for the same species, advanced aquarists tend to use scientific names for the less-common tetras. The list below is incomplete.

Adonis tetra Lepidarchus adonis
African long-finned tetra Brycinus longipinnis
African moon tetra Bathyaethiops caudomaculatus
Arnold's tetra Arnoldichthys spilopterus
Buenos Aires tetra Hyphessobrycon anisitsi
Banded tetra Astyanax fasciatus
Bandtail tetra Moenkhausia dichroura
Barred glass tetra Phenagoniates macrolepis
Bass tetra Hemigrammus rodwayi
Beacon tetra Hemigrammus ocellifer
Belgian flag tetra Hyphessobrycon heterorhabdus
Black darter tetra Poecilocharax weitzmani
Black morpho tetra Poecilocharax weitzmani
Black neon tetra Hyphessobrycon herbertaxelrodi
Black phantom tetra Hyphessobrycon megalopterus
Black tetra Gymnocorymbus ternetzi
Black tetra Gymnocorymbus thayer
Black wedge tetra Hemigrammus pulcher
Blackband tetra Hyphessobrycon scholzei
Blackedge tetra Tyttocharax madeirae
Black-flag tetra Hyphessobrycon rosaceus
Black-jacket tetra Moenkhausia takasei
Blackline tetra Hyphessobrycon scholzei
Bleeding heart tetra Hyphessobrycon erythrostigma
Bleeding heart tetra Hyphessobrycon socolofi
Blind tetra Stygichthys typhlops
Bloodfin tetra Aphyocharax anisitsi
Bloodfin tetra Aphyocharax alburnus
Blue tetra Mimagoniates microlepis
Blue tetra Tyttocharax madeirae
Blue tetra Boehlkea fredcochui
Brilliant rummynose tetra Hemigrammus bleheri
Bucktooth tetra Exodon paradoxus
Buenos Aires tetra Hyphessobrycon anisitsi
Butterfly tetra Gymnocorymbus ternetzi
Callistus tetra Hyphessobrycon eques
Calypso tetra Hyphessobrycon axelrodi
Cardinal tetra Paracheirodon axelrodi
Carlana tetra Carlana eigenmanni
Cochu's blue tetra Boehlkea fredcochui
Central tetra Astyanax aeneus
Coffee-bean tetra Hyphessobrycon takasei
Colcibolca tetra Astyanax nasutus
Congo tetra Phenacogrammus interruptus
Copper tetra Hasemania melanura
Costello tetra Hemigrammus hyanuary
Creek tetra Bryconamericus scleroparius
Creek tetra Bryconamericus terrabensis
Croaking tetra Mimagoniates inequalis
Croaking tetra Mimagoniates lateralis
Dawn tetra Hyphessobrycon eos
Dawn tetra Aphyocharax paraguayensis
Diamond tetra Moenkhausia pittieri
Discus tetra Brachychalcinus orbicularis
Disk tetra Brachychalcinus orbicularis
Disk tetra Myleus schomburgkii
Dragonfin tetra Pseudocorynopoma doriae
Ember tetra Hyphessobrycon amandae
Emperor tetra Nematobrycon palmeri
False black tetra Gymnocorymbus thayeri
False neon tetra Paracheirodon simulans
False red nose tetra Petitella georgiae
False rummynose tetra Petitella georgiae
Featherfin tetra Hemigrammus unilineatus
Firehead tetra Hemigrammus bleheri
Flag tetra Hyphessobrycon heterorhabdus
Flame tail tetra Aphyocharax erythrurus
Flame tetra Hyphessobrycon flammeus
Garnet tetra Hemigrammus pulcher
Glass tetra Moenkhausia oligolepis
Glossy tetra Moenkhausia oligolepis
Glowlight tetra Hemigrammus erythrozonus
Gold tetra Hemigrammus rodwayi
Golden tetra Hemigrammus rodwayi
Goldencrown tetra Aphyocharax alburnus
Goldspotted tetra Hyphessobrycon griemi
Gold-tailed tetra Carlastyanax aurocaudatus
Green dwarf tetra Odontocharacidium aphanes
Green neon tetra Paracheirodon simulans
Green tetra Paracheirodon simulans
Griem's tetra Hyphessobrycon griemi
Head-and-taillight tetra Hemigrammus ocellifer
January tetra Hemigrammus hyanuary
Jellybean tetra Lepidarchus adonis
Jewel tetra Hyphessobrycon eques
Jumping tetra Hemibrycon tridens
Largespot tetra Astyanax orthodus
Lemon tetra Hyphessobrycon pulchripinnis
Longfin tetra Brycinus longipinnis
Long-finned glass tetra Xenagoniates bondi
Longjaw tetra Bramocharax bransfordii
Loreto tetra Hyphessobrycon loretoensis
Mayan tetra Hyphessobrycon compressus
Mexican tetra Astyanax mexicanus
Mimic scale-eating tetra Probolodus heterostomus
Mourning tetra Brycon pesu
Naked Tetra Gymnocharacinus bergii
Neon tetra Paracheirodon innesi
Niger tetra Arnoldichthys spilopterus
Nurse tetra Brycinus nurse
Oneline tetra Nannaethiops unitaeniatus
One-line tetra Hemigrammus unilineatus
Orangefin tetra Bryconops affinis
Ornate tetra Hyphessobrycon bentosi
Panama tetra Hyphessobrycon panamensis
Penguin tetra Thayeria boehlkei
Peruvian tetra Hyphessobrycon peruvianus
Petticoat tetra Gymnocorymbus ternetzi
Phantom tetra Hyphessobrycon megalopterus
Pittier's tetra Moenkhausia pittieri
Pretty tetra Hemigrammus pulcher
Pristella tetra Pristella maxillaris
Pygmy tetra Odontostilbe dialeptura
Rainbow tetra Nematobrycon palmeri
Rainbow tetra Nematobrycon lacortei
Red eye tetra Moenkhausia sanctaefilomenae
Red phantom tetra Hyphessobrycon sweglesi
Red tetra Hyphessobrycon flammeus
Redeye tetra Moenkhausia sanctaefilomenae
Redeye tetra Moenkhausia oligolepis
Rednose tetra Hemigrammus rhodostomus
Red-nose tetra Hemigrammus bleheri
Redspotted tetra Copeina guttata
Rosy tetra Hyphessobrycon bentosi
Rosy tetra Hyphessobrycon rosaceus
Royal tetra Inpaichthys kerri
Ruby tetra Axelrodia riesei
Rummy-nose tetra Hemigrammus rhodostomus
Rummy-nose tetra Hemigrammus bleheri
Sailfin tetra Crenuchus spilurus
Savage tetra Hyphessobrycon savagei
Savanna tetra Hyphessobrycon stegemanni
Semaphore tetra Pterobrycon myrnae
Serpae tetra Hyphessobrycon eques
Sharptooth tetra Micralestes acutidens
Silver tetra Gymnocorymbus thayeri
Silver tetra Ctenobrycon spilurus
Silver tetra Micralestes acutidens
Silvertip tetra Hasemania melanura
Silvertip tetra Hasemania nana
Silver-tipped tetra Hasemania nana
Splash tetra Copella arnoldi
Splashing tetra Copella arnoldi
Spotfin tetra Hyphessobrycon socolofi
Spottail tetra Moenkhausia dichroura
Spotted tetra Copella nattereri
Swegles's tetra Hyphessobrycon sweglesi
Tailspot tetra Bryconops caudomaculatus
Tetra von Rio Hyphessobrycon flammeus
Three-lined African tetra Neolebias trilineatus
Tiete tetra Brycon insignis
Tortuguero tetra Hyphessobrycon tortuguerae
Transparent tetra Charax gibbosus
True big-scale tetra Brycinus macrolepidotus
Uruguay tetra Cheirodon interruptus
White spot tetra Aphyocharax paraguayensis
X-ray tetra Pristella maxillaris
Yellow tetra Hyphessobrycon bifasciatus
Yellow-tailed African tetra Alestopetersius caudalis
ReferencesISBN links support NWE through referral fees
Bali, N., and W. Fink. 2004. Paracheirodon simulans Animal Diversity Web. Retrieved November 14, 2007.
Nelson, J. S. 1994. Fishes of the World, 3rd edition. New York: John Wiley & Sons. ISBN 0471547131
Nelson, J. S. 2006. Fishes of the World, 4th edition. New York: John Wiley & Sons. ISBN 0471250317

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